KR20110041565A - Adhesives compatible with corrosion sensitive layers - Google Patents

Abstract

An article is provided comprising an adhesive having an acid value of less than about 5. The adhesive is selected from the group consisting of polyureas, polyamides, polyurethanes, polyesters, addition curable silicones, and combinations thereof. The adhesive is in contact with a corrosion sensitive layer selected from the group of metals and metal alloys. When the article is conditioned at about 60 ° C. and 90% relative humidity for about 21 days, the corrosion sensitive layer has a change of 20% or less from its initial electrical resistance.

Description

Adhesives Compatible with Corrosion Sensitive Layers {Adhesives Compatible with Corrosion Sensitive Layers}

Adhesives have found wide application in optical displays. Such applications include, but are not limited to, bonding polarizers to modules of liquid crystal displays (LCDs) and attaching various optical films to glass lenses of portable handheld devices (MHH). The polarizer may be in direct or indirect contact with the adhesive.

Recently, there has been an increasing tendency to introduce and combine touch panel functions in various display applications. The touch panel typically includes a corrosion sensitive layer such as a layer of indium tin oxide, a layer of coated polyethylene terephthalate film or a layer coated on glass. These coated substrates are often attached to the display module using adhesives. In some touch panel designs, the adhesive is in contact with the corrosion sensitive layer. In other display applications, the adhesive may also be in contact with a corrosion sensitive layer such as a vapor coated mirror surface or an electromagnetic interference shielding layer. These layers are also derived from metals and metal alloys which are often electrically conductive.

The present invention addresses the need for adhesives that are compatible with corrosion sensitive layers such as metals or metal alloys. That is, once the adhesive is in contact with this layer, the resistance of this layer is changed only minimally. In the present invention, the following definitions are used:

“Change” as used to describe the electrical resistance exhibited by the corrosion sensitive layer generally refers to the difference in the absolute value of the electrical resistance of the layer before or after conditioning;

“Acid value” generally refers to the acid content of the polymer and generally refers to the amount of potassium hydroxide (typically in mg) required to neutralize the acid in 1 g of the polymer according to ASTM D974;

“Additionally curable silicones” are generally reactions of vinyl-terminated oligomers / polymers, such as vinyl-terminated polydimethylsiloxanes (PDMS), in the presence of platinum catalysts, and hydride-containing oligomers / polymers, such as PDMS containing silicon hydrides. Entails;

An "adhesive" generally refers to a viscoelastic material having a viscous and elastic component such that the adhesive exhibits some restoring force under compressive stress, but this is generally not a spring-like material, ie it is not an elastic solid. Mean;

"Corrosion sensitive layer" generally means a layer that is susceptible to oxidation upon exposure to air and moisture, and when a voltage is applied to this layer, the layer can carry current;

A "cure-in-place adhesive" generally refers to a liquid system in which the adhesive components can be delivered to a desired location where they react almost spontaneously or upon exposure to an energy source (such as heat or radiation). Mean;

"Heat activated adhesives" generally do not exhibit substantial stickiness in dry form using acupressure at room temperature, but with exposure to elevated temperatures, the adhesive becomes tacky, wets the substrate surface well, and By means of an adhesive which, after cooling with water, adheres to various heterogeneous surfaces;

"Microstructure" as used to describe any general layer or substrate is generally meant to contain repeating structures that protrude from the major surface of the layer, including, but not limited to, peaks and pyramids Can be in various forms;

“Optically transparent” generally means that the material exhibits a haze of about 5% or less when measured on a sample of 25 micrometers thick in the manner described below in the Examples section;

"Pressure-sensitive adhesive" generally means that the adhesive is strong and permanently tacky in dry form at room temperature and firmly adheres to various heterogeneous surfaces.

In one aspect, the invention is selected from the group consisting of polyurea, polyamides, polyurethanes, polyesters, addition-curable silicones, and combinations thereof in contact with a corrosion sensitive layer selected from the group of metals and metal alloys, An article comprising an adhesive having an acid value of less than about 5, wherein if the article is conditioned at about 60 ° C. and 90% relative humidity for about 21 days, the corrosion sensitive layer is 20% from its initial electrical resistance. It has the following changes. In one embodiment, the adhesive and the corrosion sensitive layer are disposed on the first major surface of the substrate such that the corrosion sensitive layer and optionally the adhesive are in contact with the first major surface of the substrate.

In another aspect, the present invention provides a method comprising the steps of: (i) providing a substrate having a corrosion sensitive layer disposed on at least a portion of the substrate; (ii) from (a) a backing having opposing first and second major surfaces, (b) polyurea, polyamide, polyurethane, polyester, addition-curable silicone, and combinations thereof Providing a tape comprising an adhesive having an acid value of less than about 5 selected; And (iii) laminating the tape to the substrate such that the adhesive is in contact with the corrosion sensitive layer. The corrosion sensitive layer disclosed herein is substantially flat; That is, they do not contain microstructures. In another embodiment, if a tape is used, the backing or substrate is substantially flat.

In one exemplary application, the articles and methods of making the articles described herein can be incorporated into electronic devices such as, but not limited to, liquid crystal display panels, capacitive touch panels, cell phones, handheld devices, and laptop computers. .

Other features and advantages will be apparent from the description and claims to practice the following invention. The above summary is not intended to disclose each illustrated embodiment or every implementation of the present invention. The following detailed description more particularly exemplifies certain presently preferred embodiments using the principles disclosed herein.

The invention can be better explained with reference to the drawings:
1 is a plan view of an exemplary article according to the present invention;
2 is a cross-sectional view of another exemplary article in accordance with the present invention;
3 is a schematic view of an exemplary method of making an article according to the present invention;
4A and 4B are schematic views of another exemplary method of making an article according to the present invention;
5 is a cross-sectional view of another exemplary article in accordance with the present invention; And
6 shows the relationship of resistance change as a function of time for Examples 1-5 and control samples during various conditioning steps.
The drawings are shown to be ideal, not to scale, and are intended for illustrative purposes only.

All numbers herein are considered to be modified by the term "about." Reference to numerical ranges by endpoints includes all numbers included within that range (eg, 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5). All parts mentioned herein are by weight unless otherwise indicated.

Referring now to the drawings, FIG. 1 shows a top view of an article 1 that can be used in an electronic device. The article includes a substrate 4 having a plurality of corrosion sensitive traces 5 in the form of a grid, disposed on the first major surface of the substrate. Connector pads 6 are placed adjacent to each end of the corrosion sensitive trace. When current is applied to the connector pads, they are in electrical communication with the corrosion sensitive traces. The adhesives disclosed herein will typically be applied to the substrate such that it is in direct contact with the corrosion sensitive layer and the first major surface of the substrate.

2 shows a cross-sectional view of an exemplary article 10 having a plurality of alternating layers of substrate 14 having an adhesive 18 and a corrosion sensitive layer 15 disposed on the first surface 14a of the substrate. It is. The connector pad 16 lies adjacent to the edge of the substrate. The connector pad is in communication with the corrosion sensitive layer, allowing the pad and the corrosion sensitive layer to be in electrical communication with each other as current passes through the layer 15. Although only two sets of alternating layers of substrates and adhesives are shown, it is within the scope of the present invention to use a larger number of alternating layers or to use one set of substrates and adhesives.

3 shows a schematic of an exemplary method of making an article. The method includes providing a first substrate 24 having a discontinuous corrosion sensitive layer 25 disposed on the first surface 24a of the first substrate. The connector pad 26 lies adjacent to the substrate as shown in FIG. The roll tape 20 has an adhesive 28 coated on the backing 21. Optionally, the backing includes a release coating that causes the roll tape to unwind. The tape is applied to the first surface 24a of the first substrate 24 such that the adhesive 28 is in contact with the corrosion sensitive layer and the exposed portion of the first surface 24a, ie, the portion not covered by the corrosion sensitive layer. Are stacked. In one embodiment, the backing 21 functions as a second substrate and becomes part of the article. In another embodiment, the backing can be removed and discarded, and the second substrate can be laminated to the just exposed surface of the adhesive 28. Although FIG. 3 illustrates the use of roll tapes, this method may be practiced using cut sheet tapes.

4A and 4B show schematic diagrams of another exemplary method of making an article according to the present invention. The method includes providing a cavity 43 formed by a first substrate 44a and a second substrate 44b that may be substantially coplanar with one another. The corrosion sensitive layer 45 is disposed on at least one of the first substrate and the second substrate. The electrical connector pad 46 lies adjacent one of the two substrates and is in communication with the corrosion sensitive layer. For illustrative purposes, it has been shown that a corrosion sensitive layer is disposed on the second substrate 44b. The transport mechanism, such as the multi-chamber syringe 50, includes a first chamber 50a and a second chamber 50b in which the components of the adhesive are stored separately. In use, a user may press a plunger in a syringe, the components will be mixed in a third chamber in which the mixer is housed, and the adhesive composition 58 may be mixed. In this way, the components can be stored under stable conditions until ready for use. In FIG. 4B, the adhesive composition 58 is mixed in and dispensed from the syringe, filling the cavity. After mixing, the components can be sufficiently reactive so that they polymerize and provide the final adhesive. Optionally, an energy source 60 such as heat from an oven or an infrared light source can be used to cure the adhesive composition. This particular method has the advantage that it can better fit the non-uniform thickness between the first substrate and the second substrate while the adhesive composition is in liquid form, and when the substrate is rough. This method is particularly suitable for situations in which the first and second substrates are glass or substantially rigid transparent polymer materials.

5 shows a cross-sectional view of the multilayer article 30. The article includes a central substrate 34 having opposing first and second major surfaces 34a and 34b, respectively. A corrosion sensitive electroconductive layer 35 is placed on each of the first and second surfaces. 5 shows two consecutive layers 35, it is within the scope of the invention to have only one layer 35, which layers may be discontinuous. Optionally, an electrical connector pad (not shown) is attached to the substrate and the pad can be in communication with layer 35. Covering layer 35 is two adhesive layers 38. And, if desired, an adhesive layer may be covered with the protective liner 39.

glue

Suitable adhesives for use in the present invention include those that are neutral or basic in nature. In other words, the adhesive preferably contains no acid functionality or only traces of acid functionality such that the acid value of the adhesive is less than about 5. The acid content in the adhesive does not interfere enough to detect the electrical performance of the corrosion sensitive layer over the life of the article. Adhesives suitable for use in the present invention may be pressure sensitive adhesives (PSA), heat activated adhesives (HAA) or field cured adhesives (CIPA). In one embodiment, the adhesive is optically transparent. Thus, the adhesive can be either optically clear PSA or optically opaque PSA, optically clear HAA or optically opaque HAA, or optically clear CIPA or optically opaque CIPA.

Exemplary adhesives include polyureas, polyamides, polyurethanes, polyesters, addition curable silicones, and combinations thereof. The adhesive has an acid value of less than about 5, preferably less than 3, more preferably less than 1. The polymers disclosed herein are typically polyols extended with a multifunctional isocyanate (to make polyurethanes, polyureas or combinations thereof) or multifunctional esters (to make polyamides, polyesters or combinations thereof) or It is derived from polyamines. Polyamides can also be derived from cyclic amides (lactams) by ring-opening polymerization, but chain extension is preferred for ease of introduction of other segments. If an acid value of less than about 5 is met, the polyester may also be derived from polyols and multifunctional acid chlorides. Urea, amide, ester or urethane groups typically provide a hard, reinforced polymer segment. Strong hydrogen bonds between these groups provide cohesive strength. In some cases, short chain extenders (typically low molecular weight polyamines or polyols) may be used to provide additional hard segments. Optionally, the polymer may be terminated with terminal or structo-pendant curable groups such as, for example, silanes, acrylates, methacrylates, residual isocyanates, epoxies, and the like. Soft segments derived from polyols and polyamines with lower modulus and / or lower T _g are typically preferred to promote thermal activation of the adhesives or make them inherently tacky. Examples of these polyamines or polyols include aminopropyl functional polydimethylsiloxanes, hydroxypropyl functional polydimethylsiloxanes, polybutadiene diols, polyethylenebutylene diols, polyether diols (such as polytetrahydrofuran diols) Polyether diamines (such as Jeffamine ™), low T _g polyesters and the like. If desired, the adhesives of the present invention may be further formulated with any catalyst for tackifiers and curable groups.

Preferably, the pressure sensitive adhesive has a shear elastic modulus of 3 × 10 ⁵ Pascal or less and a glass transition temperature (T _g ) of about 10 ° C. or less at room temperature. Thermally activated adhesives typically have a shear elastic modulus of less than 5 × 10 ⁵ Pascals at a thermal activation temperature and a T _g below the thermal activation temperature. All three types of adhesives, PSA, HAA and CIPA, whether optically transparent or non-transparent, typically have elastic and viscous components in their modulus, ie the strain (strain) of the material is applied Not directly proportional to stress, there is some loss of viscosity. The adhesive can be prepared using solvent based solution polymerization or using bulk polymerization.

In solution polymerization, solvent-based adhesives, components and additives are mixed in an organic solvent, coated with solution and dried. If it is desired to coat the adhesive with a solvent, the reaction can be carried out in a suitable solvent (ie the solvent does not interfere with the polymerization reaction), or the reaction can be carried out in bulk, and the resulting polymer is suitable for coating. Dissolve in a solvent. Phase separation of hard and soft segments in polymer changes often provides a physical crosslinked network. Such networks provide high cohesive strength to polymers and coatings. In some cases, the solvent based adhesive may also be crosslinked during the drying process, or in some cases it may be crosslinked after the drying step. Such crosslinkers include heat or UV crosslinkers that are activated during or after the drying step of preparing the adhesive to be coated with the solvent. Radiation induced crosslinking such as electron beams may also be used. In addition, the polymers of the present invention may also include one or more curable groups. Examples of these curable groups include silanes or terminal isocyanates, which are typically cured by ethylenically unsaturated groups such as moisture, epoxy and acrylates, and may be cured by heat or radiation, optionally in the presence of a catalyst or initiator. The solvent based adhesive can be coated onto a suitable flexible backing material by any known coating technique to produce an adhesive coated sheet material.

In bulk polymerization, monomer premixes comprising the components of the adhesive are mixed using a static mixer, an extruder or a mechanical mixer to facilitate the intimate contact of the reagents with each other. Optionally, a catalyst such as dibutyl tin dilaurate may also be added to the mixture. Bulk polymerization as described herein is well suited for the formation of thick (eg, 0.127 to 1.016 mm (0.005 to 0.040 inch)) adhesive films for use in hard-hard lamination applications. For example, such a thick adhesive film may be laminated to one piece of glass or may be used to laminate two pieces of glass together.

In another method, the components of the adhesive are mixed with optional additives (eg tackifiers, heat stabilizers, fillers) and optional crosslinkers. The monomer or monomer mixture can be used for gap-filling applications, eg to fill the space between two substrates, such as between two glass substrates. In one application, a syringe is used to convey the adhesive component into the gap and the reagent is cured using thermal radiation. Such methods and transport mechanisms are well suited for gaps of various thicknesses or where the substrate has a surface that is not substantially flat.

The flexible backing material can be any material commonly used, such as tape backings, optical films, release liners, or any other flexible material. In the final product application, the adhesive is required to be in contact with the corrosion sensitive surface, but if it is outside the optical path, the backing need not be optically transparent. Typical examples of flexible backing materials used as tape backings that may be useful in adhesive compositions include plastic films such as polypropylene, polyethylene, polyurethane, polyvinyl chloride, polyesters (eg polyethylene terephthalate) , Cellulose acetate, and those made of ethyl cellulose. Some flexible backings may have a coating. For example, the release liner may be coated with a low adhesive component, for example silicone. Exemplary coating techniques include roll coating, spray coating, knife coating, die coating, printing, and the like. Solution treatments as described herein are well suited to making thin, eg, 25-75 micron (0.001-0.003 inch) adhesive films for use as transfer tapes. The resulting tape has a low volatility residue after oven drying.

[Example]

These examples are for illustrative purposes only and are not intended to limit the scope of the appended claims. All parts, percentages, ratios, etc. in the Examples and the rest of the specification are by weight unless otherwise indicated. Solvents and other reagents used were obtained from Sigma-Aldrich Chemical Company, Milwaukee, WI unless otherwise indicated.

Turbidity and Permeability Test

A 25 micron thick sample of the adhesive is used to prevent any bubbles from being trapped between the film and the adhesive layer, so that the 25 micron thick Mellinex® polyester film 454 (DuPont, Wilmington, DE, USA) It was laminated to the company (DuPont Company). 75 mm × 50 mm flat micro slides (glass slides from Dow Corning, Midland, Mich.), Wiped three times with isopropanol, ensure that no bubbles are trapped between the adhesive and the glass slides. It was laminated to the adhesive sample using a hand roller to ensure. Permeability and percent turbidity were measured using a model 9970 BYK Gardner TCS Plus spectrophotometer (from BYK Gardner, Columbia, Maryland). Background measurements were made using a sandwich of the Melinanex polyester film 454 and a glass slide. The transmittance and turbidity (%) of the adhesive sample were then obtained directly on the film / adhesive / glass laminate in the spectrophotometer.

Each of the adhesives of Examples 1-5 had an optical transmittance value greater than 90% and a haze value less than 5%.

ITO compatibility study of corrosion sensitive layer

The compatibility of the corrosion sensitive layer of the adhesive with the indium tin oxide (ITO) layer was done as follows. A sample of adhesive was transferred to a primed polyester (PET) backing of 0.0381 mm (0.0015 inch) thickness to form a tape. The tape was then laminated to a PET film whose major surface was coated with an ITO layer to form a laminate such that the adhesive was in direct contact with the trace. The initial surface resistance was measured on the ITO trace using an ohm meter with an electrical lead of the meter positioned across the connector pads. The resulting stacks were conditioned in an oven set at 60 ° C. and 90% relative humidity. The resistance meter was used to measure the surface resistance of each sample periodically over a period of 28 days. The average of five surface resistance measurements was recorded.

The control sample included ITO traces exposed to ambient conditions, ie no adhesive was deposited on the PET substrate with ITO containing traces.

Compatibility test with other corrosion sensitive surfaces

The compatibility of the corrosion sensitive material of the adhesive with nickel or aluminum vapor metallized PET was done as follows. A sample of adhesive was transferred to a primed polyester (PET) backing of 0.0381 mm (0.0015 inch) thickness to form a tape. The tape was then laminated to the metallized PET film with the adhesive in direct contact with nickel or aluminum. The initial light transmittance and delta (E) of the laminate were measured using a spectrophotometer (from Beike Gardner, Columbia, MD) in addition to the model 9970 BYK Gardner TCS. The resulting stacks were conditioned in an oven set at 60 ° C. and 90% relative humidity, and the light transmittance and delta (E) for each sample were measured periodically over a period of 25 days. Delta (E) is used to describe (mathematically) the distance between two colors. It is defined as the square root of the sum of (L ₁ -L ₂ ) ² , (a _1- a ₂ ) ² and (b ₁ -b ₂ ) ² , where L, a and b are color indices.

Example  One

800 g of Jeffamine D-2000 polyetheramine (from Huntsman Corp., Woodland, TX), dissolved in 600 g of isopropanol, 800 g of isopropanol, 22.35 g of Dytek® A diamine (from DuPont, Wilmington, DE) and 151.36 g of Desmodur® W monomeric cycloaliphatic diisocyanate (Bayer Materials Science Ayer, Leverkusen, Germany From Material Science AG). The resulting mixture was placed on a mechanical roller for 48 hours at room temperature. The solution was then coated onto a siliconeized polyester release liner and dried with a final pressure sensitive polyamide based adhesive having a thickness of 25 microns (0.001 inch) at 70 ° C. for 10 minutes.

Example 2

86 g of hydroxyl functionalized polybutadiene (CAS No. 69102-90-5, available from Aldrich, Milwaukee, WI) with a number average molecular weight of 2,800 was added to the reactor with 9.15 g (0.08 equivalents) of isophorone diisocyanate. Put in. The resulting mixture was allowed to react at 80 ° C. under anhydrous nitrogen atmosphere for 2 hours. 5.3 g of aminopropyl trimethoxysilane (0.21 equiv) were then added. The mixture was stirred for 10 minutes and then 66.7 g of toluene was added to produce silane terminated urethane in 60% solids solution. The solution was coated on a liner and dried at 70 ° C. for 15 minutes to a final pressure sensitive adhesive thickness of 48 microns (0.0019 inches). Because of the presence of terminal trimethoxy silane groups, such dry polymer coatings can continue to cure in the presence of moisture to provide a crosslinked polymer coating. Wet curing can be accelerated in the presence of a catalyst such as dibutyl tin dilaurate.

Example 3

150 g of Preplast® 3192, semicrystalline polyester polyol (1020 hydroxyl equivalent weight, 0.147 equivalent from Uniqema, Newcastle, Delaware) and 27.7 g of isophorone diamond in the reactor Isocyanate (0.25 equiv) was added. The resulting mixture was allowed to react at 80 ° C. under anhydrous nitrogen atmosphere for 2 hours. Then 22.3 g of aminopropyl trimethoxysilane (0.10 equiv) were added. The mixture was stirred for 10 minutes and then 66.7 g of toluene was added to produce a silane terminated urethane of 75% solids solution. The solution was coated on a liner and dried at 70 ° C. for 15 minutes to a final pressure sensitive adhesive thickness of 38 microns (0.0015 inch). Like the material of Example 2, such polymers may also be crosslinked in the presence of moisture.

Preparative Example A: Synthesis of Silicone Polyurea (SPU) Elastomers

In the reaction vessel, 33,000 PDMS diamine, Ditec A and H12MDI were placed in a sufficient amount of 2-propanol in a molar ratio of 1: 1: 2 to provide reagents of 20% solids solution. The mixture was stirred for 2 hours, giving a 20% solids silicone polyurea elastomer.

Preliminary Example B

Samples of 14K PDMS diamine (830.00 g) were placed in a two liter three-necked resin flask equipped with a mechanical stirrer, heating mantle, nitrogen inlet tube (with stopper), and outlet tube. The flask was purged with nitrogen for 15 minutes and then diethyl oxalate (33.56 g) was added dropwise with vigorous stirring. This reaction mixture was stirred at room temperature for approximately 1 hour and then at 80 ° C. for 75 minutes. The reaction flask was equipped with a distillation adapter and a receiver. The reaction mixture was heated at 120 ° C. for 2 hours and then at 130 ° C. for 30 minutes under vacuum (133 Pascal, 1 Torr) until no more distillate could be collected. The reaction mixture was cooled to room temperature to give an oxamido ester terminated silicone product (ie, silicone diamine terminated with a monoethyl oxamide ester group at both ends). Gas chromatographic analysis of the clear mobile liquid showed no detectable amount of diethyl oxalate remaining. The ester equivalent weight of this precursor for Preliminary Example C was determined by titration (equivalent weight = 8,272 g / equivalent).

Titration Methods for Equivalent Weight Determination

Approximately 10 g of the precursor compound of Example Example B was added to a jar. Approximately 50 g of THF solvent was added. The contents were mixed using a magnetic stir bar mix until the mixture was homogeneous. The theoretical equivalent weight of the precursor was calculated and then N-hexylamine was added in an amount ranging from 3 to 4 times this equivalent number. The reaction mixture was stirred for at least 4 hours. Bromophenol blue (10-20 drops) was added and the contents mixed until homogeneous. The mixture was titrated to the yellow endpoint with 1.0 N (or 0.1 N) hydrochloric acid. The equivalent number of precursors was the equivalent number of N-hexylamine added to the sample minus the equivalent number of hydrochloric acid added in the titration. Equivalent weight (g / equivalent) was the sample weight of the precursor divided by the equivalent number of precursor.

Preliminary Example C

Precursor (98.13 g) and ethylene diamine (0.36 g) of Preliminary Example B were weighed into a bottle. The bottle was sealed and the mixture was stirred rapidly until the contents were too viscous to flow. The bottle was placed on a roller mill overnight at ambient temperature. The solid product was collected.

Example 4

For Example 4, silicone polyurea from Preliminary Example A, using conventional solvent means, at 20% solids in a solvent blend of 30 wt% IPA (120.00 parts) and 70 wt% toluene (280.00 parts) Silicone polyurea elastomeric adhesives were prepared by blending an elastomer (80 parts) with additional oil (20 parts). These samples were coated with PET primed from the solvent mixture and dried to a 25 micron final thickness.

Example 5

The copolymer of preliminary example C (18.50 g) was dissolved in THF (45.60 g). MQ resin (30.83 g, 60.0% solids) was added to the polymer solution. The resulting mixture was mixed overnight at ambient conditions and then knife coated onto PET. The coated film was dried at ambient temperature for about 15 minutes and then dried in a 130 ° C. oven for 10 minutes to provide a 25 micron dry thickness coating.

FIG. 5 shows compatibility studies of the adhesive and control samples of Examples 1-5 over 28 days as described in the test method described above. As the data show, all five samples showed an increase in resistance of less than 20% after 28 days of exposure at 60 ° C. and 90% relative humidity (RH), with changes in electrical resistance of less than 20% at 21 days of exposure. Was within the goal. Although the control sample showed the smallest increase in resistance compared to the examples for use in the production apparatus contemplated herein, an adhesive would be required.

Example 6

The adhesive (25 microns) of Example 5 was laminated to two sides of a polyolefin (ExxonMobil EXACT 8210) carrier film (125 mil) to provide an adhesive transfer tape having a polyolefin core and a silicone adhesive surface.

Tables 2 and 3 show the compatibility studies of the adhesive of Example 6 on nickel and aluminum vapor metal treated PET films. The data showed minimal corrosion of the metal surface by the adhesive as indicated by the relative increase in transmittance and delta (E).

Example 7

Two silicone adhesives, Dow Corning 7657 and Dow Corning 7658 (70/30 dry weight ratio), were combined with Dow Corning Seal-Off 7678 Crosslinker (0.16 parts) and Dow Corning Seal-Off 4000 catalyst. Mixed. The mixed solution was dried on a fluorosilicone liner in a 130 ° C. oven for about 15 minutes to give a 36 micron dry thickness coating. The dried adhesive was then laminated to two sides of a polyolefin (ExxonMobil EXACT 8210) carrier film (2.54 mm (100 mil)) to provide an adhesive transfer tape.

Table 4 shows the surface resistance change when the adhesive of Example 7 is placed on the ITO surface. The data shows minimal ITO corrosion as indicated by a small increase in resistance.

Claims (20)

From the group consisting of polyureas, polyamides, polyurethanes, polyesters, addition cure silicones and combinations thereof in contact with a corrosion sensitive layer selected from the group of metals and metal alloys An article comprising an adhesive having an acid value of less than about 5, wherein the corrosion sensitive layer exhibits a change of less than 20% from its initial electrical resistance when conditioned at about 60 ° C. and 90% relative humidity for about 21 days. . The article of claim 1, wherein the corrosion sensitive layer is disposed on the first major surface of the substrate. The article of claim 2, wherein at least one of the adhesive and the substrate is optically transparent. The article of claim 2, wherein the substrate is selected from the group consisting of glass and polymer films. The article of claim 2, wherein the corrosion sensitive layer covers or substantially covers a portion of the first major surface of the substrate. The article of claim 5, wherein the corrosion sensitive layer is present in a regular pattern when the corrosion sensitive layer covers a portion of the first major surface of the substrate. The article of claim 1, wherein the corrosion sensitive layer is selected from the group consisting of copper, copper alloys, silver, silver alloys, indium tin oxide, nickel, aluminum, and antimony tin oxide. The article of claim 1, wherein the corrosion sensitive layer is substantially flat. The article of claim 2, comprising a substrate having a plurality of alternating layers of adhesive and a corrosion sensitive layer disposed on the substrate. The article of claim 2, further comprising a connector pad disposed adjacent the edge of the substrate and connected to the corrosion sensitive layer. The article of claim 2, wherein the substrate has a second major surface opposite the first major surface, each surface having a corrosion sensitive layer disposed on at least a portion thereof and an adhesive disposed on the corrosion sensitive layer. The article of claim 1, wherein the adhesive is a pressure sensitive adhesive, a heat activated adhesive or a cure in place adhesive. The article of claim 1, wherein the adhesive is a film having opposing first and second major surfaces, wherein a corrosion sensitive layer is disposed on each of the first and second surfaces of the adhesive film. Providing a substrate having a corrosion sensitive layer disposed on at least a portion of the substrate;
(i) a backing having opposing first and second major surfaces, (ii) an acid value of less than about 5, polyurea, polyamide, polyurethane, polyester, addition-curable silicones and combinations thereof Providing a tape comprising an adhesive selected from the group consisting of: And
Laminating the tape to the substrate such that the adhesive is in contact with the corrosion sensitive layer. The method of claim 14, wherein at least one of the adhesive and the substrate is optically transparent. The method of claim 14, wherein the substrate is selected from the group consisting of glass and polymer films. The method of claim 14, wherein the corrosion sensitive layer is present in a regular pattern when covered. The method of claim 14, wherein the corrosion sensitive layer is selected from the group consisting of copper, copper alloys, silver, silver alloys, indium tin oxide, nickel, aluminum, and antimony tin oxide. The method of claim 14, wherein the corrosion sensitive layer is substantially flat. The method of claim 14, further comprising a connector pad disposed adjacent the edge of the substrate and in contact with the corrosion sensitive layer.

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